1. Field of the Invention
The invention relates to a circuit arrangement including digital-to-analog current converters whose output amplitudes depend on the value of a digital data word and whose output amplitude ranges depend on the value of a bias current applied to the respective converter.
2. Description of the Related Art
In digital-to-analog current converters, a digital data word is converted into analog form. This means that an analog output current is generated in dependence on the digital value of the data word. The value of the output current then changes according as the data words change.
Furthermore, it is known from U.S. Pat. No. 5,570,090 to vary, the bias current which is applied to the digital-to-analog current converter, in dependence on a control data word. The output amplitude range that can be obtained in dependence on the values of the data words can be set by an appropriate choice of the value of this bias current, which is otherwise constant. Thus, a kind of quasi-scaling is possible.